System for adding solids to liquids under pressure



- Nov. 1, 1949- H. J. HEPP ET AL SYSTEM FOR ADDING SOLID S TO LIQUIDS UNDER PRESSURE Filed Sept. 5, 1945 INVENTORS. H. J. HEPP H. R. SAILORS A ORNEYS conduit 4 to open or close the conduit and is shown in open position. Valve 5' obviously may be of any type such as a plug valve or a gate valve, and is conventionally illustrated.

In order to keep liquid 9 from rising through conduit 4 into container 2, it is necessary to maintain the top of the liquid somewhat adjacent a predetermined elevation such as ID. A float chamber II is provided which is connected to conduit 4 by pipes I2 and I3 so that the liquid level in II is the same as in 4. Floating inside II is a float which operates a liquid level control I4. Obviously, any other type liquid level control known to the art may be employed in place of parts II to I4, inclusive.

Control I4, by means of some suitable distance control I5 chosen from among the many suitable controls available in the prior art, operates motor I6 of motor valve I'i to open or close gas line I8. Any other suitable valve controlled from a distance may be used in place of I 7. Gas line I8 leads directly into conduit 4 where the gas can oppose the liquid pressure at surface III.

The right hand end of gas line l8 receives gas from a suitable source of pressure. In many instances, the gas might be air, but the use of air is not regarded as preferable with aluminum chloride. With aluminum chloride, we prefer to use hydrogen and/0r methane as a suitable gas because it is non-reactive with the dry aluminum chloride and is not adsorbed to an extent substantially altering the properties of aluminum chloride.

In order to.ailow the liquid level III to rise, it is necessary to provide a leak between the interior of conduit 4 and the atmosphere and two alternative means for doing so are provided. Valve I9 may be opened to allow gas to leak out of pipe 20 or valve 2| may be opened to allow gas to leak out of pipe 22, or both valves I9 and 2| may be opened. Pipes 2d and 22 lead to suitable points of disposal depending on the nature of the gas employed.

In order to wash down the interior of conduit 4 and prevent a crust of material from forming around level II), a spray ring 23 is provided which directs liquid onto the walls of conduit 4 whence the liquid flows down to join liquid 9 at level III. Obviously, the liquid for ring 23 may be supplied from other sources and may be a different liquid than liquid 9, but it is preferred to withdraw some of liquid 9 from container I through bypass liquid line 24 to supply liquid to ring 23. In order to move liquid through line 24, we prefer to provide pump 25 which may be of any type and it is preferred to have a valve 26 in line 24 for purposes to be set forth later.

A pressure equalization line 21 may be provided between line I8 and container 2 for more rapid equalization of pressure between 4 and the upper portion of 2 than could be obtained. through conveyor 3 and the material in bottom of container 2. With some types of dense material in conveyor 3 and container 2, it would take too long to equalize the pressure without having pipe 21; with more permeable materials, pipe 21 may be eliminated or pipe I8 can be closed before entering container 4. We prefer to have both pipes I8 and 21 'for use of both types of materials.

In order to retain a pressure inside container 2 substantially different than atmospheric it is necessary to provide a closed covering 28 for the container.

In order that the solid material does not collect on the top of the spray ring 23, a frustoconical skirt 29 is placed above the spray ring so that the top of the skirt preferably touches the side walls of the pipe and the lower edge of the skirt is preferably inside the inner circumference of the spray ring. With aluminum chloride, the skirt is preferably as shown with an acute angle to the pipe wall of less than other angles being suited to other materials.

Operation In order to start the operation, valves 26 and 5' are :closed and cover 28 of hopper 2 is removed and the hopper is filled with a granular or powdered material such as aluminum chloride. Cover 28 is then replaced and secured tightly to close container 2. Valves 26 and 5' are opened and liquid 9 flows from container I up into conduit 4 actuating liquid level control I4 to open Valve I7. Gas then passes through pipe I8 to press against liquid 9 at surface In and prevent further rise of liquid 9. At the same time, the gas from pipe I8 goes up into container 2 either through conveyor 3 or pipe 21 when the latter is provided, or both. Valve I9 or 2| or both being open, some of the gas leaks out of the pipe 20. or or both allowing the liquid 9 to rise and open valve Il' every now and then. Whereupon the gas drives liquid 9 down and liquid level control shuts valve II. In this manner, level I8 is maintained substantially at a predetermined level such as Iii.

When fumes of a reactive nature tend to rise off surface I9, it is better to open bleed valve 2| so that gas from I8 will carry the reactive vapor from It out pipe 22. Thereby, in great measure, preventing the vapor from reacting with the solid material in container 2. In other cases, valve 2| may be closed and valve I9 opened which minimizes disturbing the solid material falling through conduit 4.

The liqud 9 flowing in container I from left to right picks up the solid material falling through conduit 4 and takes it along to the right of the drawing.

Metering system 3 is provided for dumping measured amounts or rates of the solids into condu't 4 and metering means 3 may be operated intermittently, but preferably is operated continuously by any suitable variable speed means such as motor 5.

With certain solid materials, the solid materials tend to cake up and form a crust around the edge of surface It or walls of conduit 4, but we have found that such a crust can be prevented by spraying a suitable liquid on inner walls of conduit 4 to wash down the solid material into liquid 9 by a spray such as ring 23. One means of supplying liquid to ring 23, shown as pump 25, pumps liquid 9 from container I to ring 23.

When all the solid material in container 2 is exhausted, then valves 5' and 26 should be closed and the operations repeated.

By suitably changing the pressure maintenance system II to I8, this same apparatus may be applied to a system under a vacuum. For example, a steam ejector on pipe I8, could be a suitable method of vacuum maintenance and then the flow would be reversed in pipes 20, 22, and I8 from the direction indicated in the drawing by the arrows. Valve I1 and control I4 would have to be oppositely connected as the rise of surface It should shut off the vacuum at I! instead of turning on the pressure at II as shown. Gas would be leaking into conduit 4 through 7 valves I9 and 2| and if the air was bad for the process, suitable sources of inert gas would have to be provided attached to pipes 20 and 22.

While we have described one specific embodiment of our invention, the invention is not limited thereby as obviously numerous substitutions and changes of non-inventive nature may be made without departing from the spirit of our invention which is defined in the following claims.

Having described our invention, we claim:

1. A feeding system for feeding solids into a liquid under pressure comprising a first chamher for said solids, a second chamber for said liquid, a first conduit connecting said chambers, said liquid under said pressure extending from said second chamber to a liquid level in said first conduit, a feeding means for feeding said solid material through said first conduit from said first chamber to said liquid, and means for preventing said liquid from contact ng said solid material in said feeding means com; rising a second pressure gas supply conduit connected to discharge gas under pressure into said first conduit, a motor operated valve for controlling flow of gas in said second conduit, said first conduit having a restricted outlet for said gas and means actuated by said liquid level in said first conduit for controlling said motor operated valve to regulate said flow of gas into said first conduit to keep said liquid level down in said first conduit and thereby prevent said liquid from contacting said solid material in said feeding means.

2. A feeding system for feeding solids into a liquid under pressure comprising a first chamber for said solids, a second chamber for said liquid, a-first conduit connecting said chambers, said liquid under said pressure extending from said second chamber to a liquid level in said first :conduit, a feeding means for feeding said solid material through said first conduit from said first chamber to said liquid, and means for preventing said liquid from contacting said solid material in said feeding means comprising a second pressure gas supply conduit connected to discharge gas under pressure into said first conduit, a motor operated valve for controlling flow of gas in said second conduit, said first conduit having a restricted outlet for said gas whereby any vapors of said liquid are swept away before reaching said solid material in said feeding means, washing means disposed and operable for washing down a portion of the Walls of said first conduit with said liquid drawn from said second chamber and means actuated by said liquid level in said first conduit for controlling said motor operated valve to regulate said flow of gas into said first conduit to keep said liquid level down in said first conduit and thereby prevent said liquid from contacting said solid material in said feeding means.

HAROLD J. HEPP.

HOWARD R. SAILORS.

' REFERENCES crrsn The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,565,249 Berry Dec. 15, 1925 1,947,852 Jewett Feb. 20, 1934 2,272,979 Marshall et a1. Feb. 10, 1942 2,441,820 Jewell May 18, 1948 

